/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.ignite.internal.sql.engine.rel;

import java.util.List;
import org.apache.calcite.plan.RelOptCluster;
import org.apache.calcite.plan.RelTraitSet;
import org.apache.calcite.rel.RelDistributions;
import org.apache.calcite.rel.RelInput;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.RelWriter;
import org.apache.calcite.rel.SingleRel;
import org.apache.calcite.sql.SqlExplainLevel;
import org.apache.calcite.util.Pair;
import org.apache.ignite.internal.sql.engine.trait.DistributionTraitDef;
import org.apache.ignite.internal.sql.engine.trait.IgniteDistribution;

/**
 * Relational expression that iterates over its input and sends elements to remote {@link IgniteReceiver}.
 */
public class IgniteSender extends SingleRel implements IgniteRel {
    private final long exchangeId;

    private final long targetFragmentId;

    private final IgniteDistribution distribution;

    /**
     * Creates a Sender.
     *
     * @param cluster          Cluster that this relational expression belongs to
     * @param traits           Traits of this relational expression
     * @param input            input relational expression
     * @param exchangeId       Exchange ID.
     * @param targetFragmentId Target fragment ID.
     */
    public IgniteSender(RelOptCluster cluster, RelTraitSet traits, RelNode input, long exchangeId,
            long targetFragmentId, IgniteDistribution distribution) {
        super(cluster, traits, input);

        assert traitSet.containsIfApplicable(distribution)
                : "traits=" + traitSet + ", distribution" + distribution;
        assert distribution != RelDistributions.ANY;

        this.exchangeId = exchangeId;
        this.targetFragmentId = targetFragmentId;
        this.distribution = distribution;
    }

    /**
     * Constructor.
     * TODO Documentation https://issues.apache.org/jira/browse/IGNITE-15859
     */
    public IgniteSender(RelInput input) {
        this(
                input.getCluster(),
                input.getTraitSet()
                        .replace(input.getDistribution())
                        .replace(IgniteConvention.INSTANCE),
                input.getInput(),
                ((Number) input.get("exchangeId")).longValue(),
                ((Number) input.get("targetFragmentId")).longValue(),
                (IgniteDistribution) input.getDistribution());
    }

    /**
     * Get exchange id.
     * TODO Documentation https://issues.apache.org/jira/browse/IGNITE-15859
     */
    public long exchangeId() {
        return exchangeId;
    }

    /**
     * Get target fragment id.
     * TODO Documentation https://issues.apache.org/jira/browse/IGNITE-15859
     */
    public long targetFragmentId() {
        return targetFragmentId;
    }

    /** {@inheritDoc} */
    @Override
    public RelNode copy(RelTraitSet traitSet, List<RelNode> inputs) {
        return new IgniteSender(getCluster(), traitSet, sole(inputs), exchangeId, targetFragmentId, distribution);
    }

    /** {@inheritDoc} */
    @Override
    public <T> T accept(IgniteRelVisitor<T> visitor) {
        return visitor.visit(this);
    }

    /** {@inheritDoc} */
    @Override
    public IgniteDistribution distribution() {
        return distribution;
    }

    /**
     * Get node distribution.
     */
    public IgniteDistribution sourceDistribution() {
        return input.getTraitSet().getTrait(DistributionTraitDef.INSTANCE);
    }

    /** {@inheritDoc} */
    @Override
    public RelWriter explainTerms(RelWriter pw) {
        RelWriter writer = super.explainTerms(pw);

        if (pw.getDetailLevel() != SqlExplainLevel.ALL_ATTRIBUTES) {
            return writer;
        }

        return writer
                .item("exchangeId", exchangeId)
                .item("targetFragmentId", targetFragmentId)
                .item("distribution", distribution());
    }

    /** {@inheritDoc} */
    @Override
    public Pair<RelTraitSet, List<RelTraitSet>> passThroughTraits(
            RelTraitSet required) {
        throw new RuntimeException(getClass().getName()
                + "#passThroughTraits() is not implemented.");
    }

    /** {@inheritDoc} */
    @Override
    public Pair<RelTraitSet, List<RelTraitSet>> deriveTraits(
            RelTraitSet childTraits, int childId) {
        throw new RuntimeException(getClass().getName()
                + "#deriveTraits() is not implemented.");
    }

    /** {@inheritDoc} */
    @Override
    public IgniteRel clone(RelOptCluster cluster, List<IgniteRel> inputs) {
        return new IgniteSender(cluster, getTraitSet(), sole(inputs), exchangeId(), targetFragmentId(), distribution());
    }
}
